Whether the cell type is autologous or allogeneic cell, the route to administration will fit into either a one-to-one model, that is, one donor provides a source of cells that are administered to one patient (autologous or allogeneic) or a one-to-many model where one donor services many patients (allogeneic only).

2. Disease prevalence

Consider 3 types of disease prevalence: low (orphan), medium and high. It is possible that each of these could be treated using a one-to-many approach, though for high prevalence indications it is likely that a scale friendly 3-D culture approach will be needed to meet demand cost effectively.

One-to-one cell therapies, no matter how they are manufactured, require an intense service model for delivery that limits their use currently to low and medium prevalence diseases.

3. Delivery mechanism

We have defined two cell therapy delivery mechanisms, a procedure or a product. A cell therapy developed as a procedure would require a surgical intervention whereas a cell therapy developed as a product can be delivered by a skilled nurse (for example, intravenous delivery).

For acute trauma, an ‘off the shelf’ cell therapy will be the only solution no matter how it is administered. This means only a one-to-many cell therapy will suffice.

For chronic disease with elective intervention, either one-to-one or one to many cell therapies may be used. One-to-many cell therapies that are products will not require that batch manufacture is scheduled alongside the elective intervention and one-to-many cell therapies which are procedures will require only one surgical visit.

One-to-one cell therapies to treat chronic disease required two rounds of scheduled intervention, the first to procure the cell sample which will always be a procedure. The timing of the second intervention is dependent on cell culture growth rate and will require sophisticated scheduling. Though this is achievable, the cost of rescheduling a procedure will be much higher than the cost of rescheduling delivery of a product. If the risk of failure of cell culture and the consequence of multiple doses are accounted for here, then the scheduling demands become much higher and much more demanding.

It is routine in industry to consider all these factors before beginning product development as the priority, alongside treating disease, is to make a return on investment. Academics do not begin with this motivation; that is, their aim is solely to treat or cure disease. That said, the failure of an efficacious cell therapy at a late stage in development because it cannot be produced cost effectively would be disastrous. Most importantly, if cell therapies are the next step in the evolution of healthcare, then no-one should think of their cell therapy in isolation, as a bespoke treatment; moreover they should consider all ten routes to the patient in thinking about how this whole new industry will emerge.